<template>
  <el-breadcrumb class="app-breadcrumb" separator="/">
    <transition-group name="breadcrumb">
      <el-breadcrumb-item v-for="(item, index) in levelList" :key="item.path">
        <span
          v-if="item.redirect === 'noRedirect' || index == levelList.length - 1"
          class="no-redirect"
          >{{ item.meta.title }}</span
        >
        <a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script setup>
  const route = useRoute();
  const router = useRouter();
  const levelList = ref([]);

  function getBreadcrumb() {
    // only show routes with meta.title
    let matched = route.matched.filter((item) => item.meta && item.meta.title);
    const first = matched[0];
    // 判断是否为首页
    if (!isDashboard(first)) {
      matched = [{ path: "/index", meta: { title: "首页" } }].concat(matched);
    }

    levelList.value = matched.filter(
      (item) => item.meta && item.meta.title && item.meta.breadcrumb !== false
    );
  }
  function isDashboard(route) {
    const name = route && route.name;
    if (!name) {
      return false;
    }
    return name.trim() === "Index";
  }
  function handleLink(item) {
    const { redirect, path } = item;
    if (redirect) {
      router.push(redirect);
      return;
    }
    router.push(path);
  }

  watchEffect(() => {
    // if you go to the redirect page, do not update the breadcrumbs
    if (route.path.startsWith("/redirect/")) {
      return;
    }
    getBreadcrumb();
  });
  getBreadcrumb();
</script>

<style lang="scss" scoped>
  .app-breadcrumb.el-breadcrumb {
    display: inline-block;
    font-size: 14px;
    line-height: 50px;
    margin-left: 8px;

    .no-redirect {
      color: #97a8be;
      cursor: text;
    }
  }
</style>
